It would be of considerable interest if the relatively high molecular weight polyhydroxyl compounds known in polyurethane chemistry, which are generally insoluble and cannot be dispersed in water, were available in water-dispersible form because aqueous dispersions such as these would open up virtually every potential application for which, hitherto solutions of polyhydroxyl compounds in organic solvents have been used. In conjunction with blocked polyisocyanates, the aqueous dispersions could be used, in particular, for the production of coatings, films and impregnations. When dried, only water would evaporate, so that film-forming and sheet-forming systems of this type would be decidedly beneficial to the environment.
In foaming processes, in which water is in any case used as blowing agent, aqueous dipersions of polyhydroxyl compounds added to the conventional liquid polyols could also influence the properties of the hardened foams to a very considerable extent.